How To Measure Diesel RPM

[zzvyb6]

Thanks for the advice. I went to the Harbour Freight website for the photo tack and almost had it ordered (+9.99 shipping). I was curious about where a store was and low and behold, there's one 28 minutes from here. Set the TomTom for cruisin' and headed out. They had the Photo Tach in stock (I called first to confirm).

I know there's a thread here for HF Tools that Don't pass muster, but I have to admit I stayed there 2 hours longer than I planned. It wasn't just for the blond in the short shorts, either....

 

[dave1949]

, but I have to admit I stayed there 2 hours longer than I planned. It wasn't just for the blond in the short shorts, either....

Ain't Summer a great time of year? :laughing:
Dave.

 

[Soundguy]

Thanks for the advice. I went to the Harbour Freight website for the photo tack and almost had it ordered (+9.99 shipping). I was curious about where a store was and low and behold, there's one 28 minutes from here. Set the TomTom for cruisin' and headed out. They had the Photo Tach in stock (I called first to confirm).

I know there's a thread here for HF Tools that Don't pass muster, but I have to admit I stayed there 2 hours longer than I planned. It wasn't just for the blond in the short shorts, either....

hey.. that's like an adult male toy store.

I know there is a good deal of junk there.. but on the other hand.. there truly are somegood deals especially for a tool you may only use once.. or for the hobbiest who needs a set of tools for tractor maintenance vs making a living off them.

i bout a decnt 3/4 set of breaker bar and ratchet, with 3 and 6" extension, plus sockets from 7/8 thru 2.5" for a whopping 28$ a few ys ago. couldn't touch that anywhere else for that price. metal ont he BB and ratchet is 1" pared down to 3/4. I've had an 8' pipe on them with me and a buddy pulling on it to do stuff and the pipe flexed but not the BB.

soundguy

 

[JC-jetro]

All the suggestion made are good ones but as far as safety is concerned nothing is better than strobe-light tachometer, although it is pricey. I bought one for work many years ago just under $1000. I can get close (safe distance) to a rotating mechanical equipment, shine the light on any rotating part on pumps, fans and motor and adjust the frequency in which the light strobes by a knob. Once the target is motion less then rotational speed is the same as readout on the device. Can read rpm on fan motor and fan pulley safely in few second.


JC,

just one for reference,

Strobelight Tachometer. 1542-B Strobe Tachometer. RPM Measurement.

 

[Soundguy]

at 1000$ it pretty much prices it out of this world for the hobbiest who doesn't have a business of reading moving parts speeds...

hopefully the OP will be safe in whatever manner he chooses to test his rpm.

soundguy

 

[JC-jetro]

at 1000$ it pretty much prices it out of this world for the hobbiest who doesn't have a business of reading moving parts speeds...

hopefully the OP will be safe in whatever manner he chooses to test his rpm.

soundguy

Absolutely correct. I could not justify it for home use as well. I'd go to HF as well. I'm very much in to enforcing lock out/ tag out in my projects. I have used the optical drive myself too but I do want to make sure that I throw the disconnect off and have it locked out so I can safely put the reflective tape on motpr shaft, etc. One of our maintenance guys at work got so close to getting his finger stuck in motor sheave when the motor started running while he was trying to put the tape on..:shocked: he came pretty close.

I'd suggest to OP to make sure do a dry run with the engine off , figure out where is the best place to put the reflective tape on, clean the surface so the tape would not come off.

JC,

 

[RobertN]

I test fan heatsinks for PC's fairly often at work. Although most are four wire now, with their own tach output, we still verify with second source. We used to use strobe-light tachs. Too expensive though, and a hassle to use. At least compared to a laser tach.

Our little Monarch laser tachs are cheap(relatively) at less than $250. And, are calibrated(we keep ongoing yearly calibrations too).

The laser tach is instantaneous too. Well, you do have to put a piece of tape on whatever you are measuring.

All the suggestion made are good ones but as far as safety is concerned nothing is better than strobe-light tachometer, although it is pricey. I bought one for work many years ago just under $1000. I can get close (safe distance) to a rotating mechanical equipment, shine the light on any rotating part on pumps, fans and motor and adjust the frequency in which the light strobes by a knob. Once the target is motion less then rotational speed is the same as readout on the device. Can read rpm on fan motor and fan pulley safely in few second.

 

[Treemonkey1000]

I am fortunate enough to work in a calibration lab that we certify mechanical and optical tachs along with a ton of other electronic equipment items.. Even a few percent error is no big deal for the tractor stuff or other rotating items. The Lock out tag out might not be a known factor to a lot of folks.. I have to recertify on lock out tag out each year. Some of the high voltage power systems I work on will run small factories. :confused2:

 

[JC-jetro]

There is a ton of good information that is being dispersed here every day. I was just merely pointing out one option not talked about that is very viable.

JC,


For whom who have not heard of Lock out/Tag out. in order to avoid live circuit injuries or death during repair or modification one would throw out the electrical disconnect to off position or turn off a circuit breaker, use a special locking device including pad lock to lock and would leave an identification tag as to who had done it. The person who is doing the work holds on to the key for obvious reason.

 

[Soundguy]

we have a similar program at work. if we have equipment in the shop that is down for repair, and it has guards on rotating parts that are removed, the machine needs an out of service tag.. otherwise if osha inspected and saw a machine with an open belt, etc.. we could be fined. didn't matter if it had all the pistons out and the oil pan dropped..

soundguy